9900K 2 cores higher than other?

[kimccino]

Hi,

Yesterday, I bought 9900K on Gigabyte z390 Aorus Pro with Noctua NH-D15.

I ran Prime95 and specifically core #2 and #4 were 88 degrees and others were 81~83.
The image below is with AVX off.
https://drive.google.com/open?id=1nyftLcLlEYCWdE9yO1IX_Sphl7IGz5y2
(edit, image wasnt working so I just linked my google drive)
It is still the core 2 and 4 that is higher.

edit. image below is AVX on.
https://drive.google.com/open?id=1ZYu0hTEeVdBlQImXJH2Dv5RTUizXUkLt
this is like 3 min in to Prime95, by the looks of temps slowly rising, I feel like 2 and 4 might fail after 10 hours or so even at stock.

At idle, all cores are 29~32. Is it my thermal paste not evenly applied? Or is this very common??

 

[Dragos Manea]

Yes, it can be even 10 degrees difference between cores, my cpu has 58-59 on core 0,6,8,9, 64-68 degrees on core 1,2,5 and 77-78 on core 3,4,7

 

[kimccino]

Yes, it can be even 10 degrees difference between cores, my cpu has 58-59 on core 0,6,8,9, 64-68 degrees on core 1,2,5 and 77-78 on core 3,4,7

Wow, thats pretty big gap, thanks for sharing, now I can sleep better at night.

 

[kadec.a.mackinney]

some cpu's have the first few cores run at higher frequencies at stock. my 4790k runs with the first 2 cores on 4.4 whilst the 3 and 4th run at 4.3 and 4.2 respectively. this may be the case with your cpu but i am not sure. you can check this in bios if you want.

 

[Dragos Manea]

some cpu's have the first few cores run at higher frequencies at stock. my 4790k runs with the first 2 cores on 4.4 whilst the 3 and 4th run at 4.3 and 4.2 respectively. this may be the case with your cpu but i am not sure. you can check this in bios if you want.

not really, mine is manual OCed to 4.4 and still got a very big gap. This si due to core effciency, some cores are more efficient then others and needs less voltage to reach that frequency, at least this is why i ahve such a big thermal gap, my core voltage varies from 1.34V for most effcient core to 1.43V the worst effcient core. Also thermal dissipation is major factor, some cores have alittle bit more space to dissipate heat then others. There are dozens of reasons for which a core can be hotter then the others but it is very normal and it is nothing to worry about.